Field
Apparatuses and methods consistent with exemplary embodiments relate to a wireless communication system including a communication apparatus and a data communication method thereof, and more particularly, to a wireless communication system including a communication apparatus which communicates using a link adaptation method and a data communication method thereof.
Description of the Related Art
Recently, along with development of information and communication technologies, various wireless communication technologies have been developed. Among them, a wireless local area network (WLAN) is a technology for wirelessly accessing the Internet wirelessly using portable terminal devices, such as smart phones, tablet personal computers (PCs), laptop computers, and portable multimedia players located within a predetermined distance from an access point (AP).
Institute of Electrical and Electronics Engineers (IEEE) provides various standards regarding WLAN technology. A recent technology standard use model includes IEEE 802.11n, which has the maximum transmission speed of 600 Mbps. In addition, an initial radio wave arrival distance of 10 m or less is now increased to 50 m to 200 m More specifically, IEEE 802.11n adds a frame integration technology of a Multiple Input and Multiple Output (MIMO), a physical layer having a channel bandwidth of 40 MHz, and a media access layer (MAC) layer to 802.11 standards.
However, a higher bit transmission speed can transfer more data during a unit time period but provide a lower throughput at a loss link. In general, a lower bit transmission speed has a lower loss possibility. Communication systems require data transmission to be efficient and at an appropriate transmission speed. One of efficient data transmission methods is link adaptation. Link adaptation is a process of increasing a data throughput at a highest possible transmission speed using a particular modulation and coding scheme in a given link quality.
The link adaptation method includes an AutoRate Fallback (ARF) scheme, and a Receiver Based Auto Rate (RBAR) scheme based on Request-To-Send/Clear-To-Send (RTS/CTS). However, the ARF scheme is heuristic and cannot deal with quickly changing wireless channel conditions. The RBAR scheme adds a lot of changes to the IEEE 802.11 standards and consumes a large amount of wireless resources. Therefore, there is a need for technologies providing effective data transmission while being capable of promptly dealing with an instant change in a channel.